Method for writing spiral reference servo signal in hard disk drive and method for compensating for temperature

a reference servo and hard disk drive technology, applied in the direction of magnetic recording, data recording, instruments, etc., can solve the problems of hard disk drive production efficiency degradation and difficult to obtain the correct final servo signal

Inactive Publication Date: 2008-01-22
SAMSUNG ELECTRONICS CO LTD
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  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Benefits of technology

[0023]The present invention provides a method for compensating for a thermal expansion of a disk, by which an error due to a temperature change is compensated for in writing a spiral reference servo signal suitable for self-servo writing on the disk of a hard disk drive.

Problems solved by technology

Furthermore, the use of the positioner and the encoder greatly increases costs related to the servo writing process, so that efficiency in production of the hard disk drive is deteriorated.
As a result, the servo copy process is performed based on the spiral reference servo signal having a broken sync, so that a correct final servo signal is hard to obtain.

Method used

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  • Method for writing spiral reference servo signal in hard disk drive and method for compensating for temperature
  • Method for writing spiral reference servo signal in hard disk drive and method for compensating for temperature
  • Method for writing spiral reference servo signal in hard disk drive and method for compensating for temperature

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Embodiment Construction

[0035]Referring to FIG. 4, the read / write head 12 (refer to FIG. 1) is driven by a push pin. The push pin is typically moved by a positioner (not shown) driven by a high precision motor or a voice coil motor. In order to maintain a constant bit interval of a spiral reference servo signal, the read / write head 12 must move at a constant speed (as shown in a particular inclination in FIG. 4) between the reference tracks R1 and R2 (refer to FIG. 1).

[0036]The read / write head 12 is driven from an index at a point T0 and has a constant speed from a point T1 when the read / write head 12 arrives at the first reference track R1. The speed is maintained until the read / write head 12 arrives at the second reference track R2. The read / write head 12 decelerates when it arrives at the second reference track R2. These operations are repeated with respect to all spiral tracks and the spiral reference servo signal is written in a section between the first and second reference tracks R1 and R2. A series...

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Abstract

A method for writing a spiral reference servo signal suitable for a self-servo writing method in a hard disk drive includes writing a first reference pattern in an end direction of a spiral reference servo signal writing concentrically on the disk; writing a spiral reference servo signal on a current spiral track from a reference writing start position of the current spiral track; detecting a moving angle of a head to the first reference pattern, which corresponds to a distance from the reference writing start position to a reference writing end position of the spiral reference servo signal in the case that thermal expansion of the disk does not exist; compensating for a driving speed of the head with reference to the detected moving angle of the head; and writing the spiral reference servo signal on a next spiral track at a compensated driving speed of the head.

Description

[0001]This application claims priority from Korean Patent Application No. 10-2004-0094555, filed on Nov. 18, 2004, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]Methods consistent with the present invention relate to writing a reference servo signal for a hard disk drive, and more particularly, to writing a spiral reference servo signal which can compensate for an error due to a thermal expansion of a disk, and to compensating for the thermal expansion of a disk due to a temperature change.[0004]2. Description of the Related Art[0005]In general, a hard disk drive that is one of data storage devices reproduces data written on a disk or writes user data on the disk using a magnetic head, and thus, contributes to a computer system operation. As the hard disk drive becomes compact with high capacity and high density, a bit per inch (BPI) that is, a de...

Claims

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Application Information

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Patent Type & AuthorityPatents(United States)
IPC IPC(8): G11B21/02
CPCG11B5/59633G11B5/59661G11B5/012G11B5/02
InventorKIM, CHEOL-SOONSHIM, JUN-SEOKPARK, SUNG-WON
OwnerSAMSUNG ELECTRONICS CO LTD